In APS, definition, diagnosis, and evidence must not be conflated.
Definition concerns what life is: viability-oriented, constraint-closed organisation sustained through ongoing self-maintaining activity.
Diagnosis concerns how such organisation is identified. In APS, diagnosis evaluates whether a system maintains, restores, or reorganises viability under conditions of perturbation and vulnerability.
Evidence consists of observable indicators supporting inference to organised persistence. These may include endogenous repair, coordinated regulation, metabolic integration, adaptive reorganisation, and viability-oriented modulation of activity. None of these defines life by itself; their significance lies in what they reveal about the underlying organisation of the system.
APS therefore treats biological evidence not as a checklist of traits but as evidence for underlying organisational conditions. A system may move without being alive, regulate without exhibiting biological agency, or display complex behaviour without sustaining its own organised persistence. For this reason, APS asks not merely what a system does, but how its organisation contributes to maintaining its continued existence.
Key Point: Biological evidence supports inference to viability-oriented organised persistence. Activity, complexity, regulation, or behavioural sophistication become biologically significant only insofar as they contribute to the maintenance of a persistence architecture capable of sustaining its own viability.